This document provides a summary of a book on second language acquisition. It discusses the author's background and motivation for writing the book. The book is organized into three parts that cover universal influences on SLA, factors explaining individual differences, and the social dimensions of language learning. Some strengths of the book are that it presents many insights from an interdisciplinary perspective and points to potential new areas of research. Some issues that could be improved are reducing technical jargon, including a glossary, streamlining sections, and considering separate books for graduate students versus researchers.